<!DOCTYPE html>
<html>
  <head>
    <meta charset="utf-8">
    <title></title>
    <script type="text/javascript">
      function *show(x,y)
      {
        alert(x + ' ' + y);
        alert('a');

        let a = yield;

        alert('b');
        alert(a);
      }

      let gen = show(1,99);
      gen.next(12);
      gen.next(5);
    </script>
  </head>
  <body>

  </body>
</html>
